title: Desensitization of FSH-responsive adenylyl cyclase in cultured immature Sertoli cells by homologous hormone.
abstract: Sertoli cell monolayers were prepared from 19-day-old rat testes. On day 7 of culture cells were incubated for 24 hr in the presence or absence of ovine follicle stimulating hormone (oFSH). Cells were harvested, and adenylyl cyclase responses of the membrane particles to FSH, human chorionic gonadotropin (hCG), isoproterenol, and fluoride (F-) were examined in the presence of either GTP or the nonhydrolyzable guanylyl nucleotide GMP-P(NH)P. Culturing the cells in presence of FSH  caused a hormone specific desensitization of FSH-responsive adenylyl cyclase, whereas responses to isoproterenol and fluoride were unaffected. Activation of Sertoli cell adenylyl cyclase by GTP and GMP-P(NH)P showed no difference between cells preincubated with or without FSH, indicating that FSH did not change the activity of the G/F (or N) component or its interaction with the catalytic subunit of the adenylyl cyclase. FSH-responsive adenylyl cyclase in cultured Sertoli cells has been shown to be selectively desensitized by homologous hormone. The mechanism may involve alteration or loss of the FSH receptor or changes in the "coupling" of the FSH receptors to the G/F component of the adenylyl cyclase, since there was no alteration in the guanylyl nucleotide and fluoride activation.
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012708:Sertoli Cells / Q000201:enzymology*; D012969:Sodium Fluoride / Q000494:pharmacology
chemical_list: D006063:Chorionic Gonadotropin; D006165:Guanylyl Imidodiphosphate; D012969:Sodium Fluoride; D005640:Follicle Stimulating Hormone; D000262:Adenylyl Cyclases; D007545:Isoproterenol